Download Chapter 1: The Earth`s Atmosphere Overview of the Earth`s

Chapter 1: The
Earth’s Atmosphere
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Overview of the Earth’
Earth’s atmosphere
Vertical structure of the atmosphere
Weather and climate
Overview of the
Earth’s Atmosphere
• The atmosphere, when scaled to the size of an
apple, is no thicker than the skin on an apple.
Composition of the
Atmosphere
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permanent gases
• roles of nitrogen and oxygen
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variable gases
• role of water vapor
Table 1-1, p. 3
Composition of the
Atmosphere
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Carbon dioxide and the greenhouse gases
ozone
aerosols
pollutants
• Ozone at high altitudes (stratosphere) is “good”
good”;
ozone at low altitudes (troposphere) is “bad.”
bad.”
Fig. 1-2, p. 3
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FIGURE 1.3 The main
components of the
atmospheric carbon
dioxide cycle. The gray
lines show processes
that put carbon dioxide
into the atmosphere,
whereas the red lines
show processes that
remove carbon dioxide
from the atmosphere.
Keeling curve of CO2 since 1958
Stepped Art
Fig. 1-3, p. 4
Fig. 1-4, p. 5
Figure 1.5: The darkest
color represents the area
of lowest ozone
concentration, or ozone
hole over the Southern
Hemisphere on
September 22, 2004.
Notice that the hole is
larger than the continent
of Antarctica. A Dobson
Unit (DU) is the physical
thickness of the ozone
layer if it were brought
to the earth’s surface,
where 500 DU equals 5
millimeters.
Volcanoes contribute
particulates and aerosols to
the atmosphere
Fig. 1-5, p. 6
The Early Atmosphere
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the first atmosphere (H and He)
outgassing and the second atmosphere
evolution of the atmosphere: carbon
dioxide and oxygen
Fig. 1-6, p. 6
Vertical Structure of
the Earth’s
Atmosphere
• The evolution of life and the atmosphere are closely
linked.
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A Brief Look at Air Pressure
and Air Density
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air density
air pressure
seasea-level pressure
• Baseballs travel farther in higherhigher-altitude air (Denver)
than they do in lowerlower-altitude air.
Fig. 1-7, p. 8
Layers of the Atmosphere
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1013.25 mb =
„
29.92 in Hg
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~14.7 lbs/in2
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vertical temperature profile
troposphere
stratosphere
mesosphere
thermosphere
• Temperatures, winds,
humidity and pressures high
above the ground are
measured twicetwice-daily by
radiosonde.
radiosonde.
Fig. 1-8, p. 9
The Ionosphere
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electrified regions of the atmosphere
D, E and F regions
radio waves
• When the radio was invented by G. Marconi in the
early 20th century, it was not known how radio
waves traveled long distances through the
atmosphere.
Fig. 1-11, p. 13
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Weather and Climate
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Fig. 1-11, p. 13
Elements of Weather
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air temperature
air pressure
humidity
clouds
precipitation
visibility
wind
Climate
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• Certain weather elements, like
clouds, visibility and wind, are
of particular interest to pilots.
A Satellite’s View of the
Weather
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average weather
extremes
Storms of all Sizes
geostationary satellites
„
• Atmospheric observation
from satellites was an
important technological
development in
meteorology. Other
important developments
include computers, internet,
and Doppler radar.
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midlatitude cyclonic storms
hurricanes and tropical storms
thunderstorms
tornadoes
• Storms are very exciting, but they also play an
important role in moving heat and moisture around
throughout the atmosphere.
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A Look at a Weather Map
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wind speed and direction
cyclones and anticyclones
fronts
• Wind direction is defined in the opposite way as
ocean currents: a southerly current means water is
moving towards the south.
Fig. 1-13, p. 17
Weather and Climate in our
Lives
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wind chill, frostbite and hypothermia
heat exhaustion and heat stroke
cold spells, dry spells and heat waves
severe thunderstorms and flash floods
• The mathematical formula for determining the wind
chill temperature has recently been revised due to new
experiments.
Fig. 1-16, p. 19
Mike Salsbury, The
Chronicle
A Centralia
neighborhood near
Mellen Street sits
flooded Tuesday as a
result of severe storms
that caused record flood
levels on the Chehalis
River.
April, 1997 Red River flood--Grand Forks, North Dakota
Fig. 1-18, p. 20
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The Chehalis River floods large areas of Chehalis, and also submerges
several sections of Interstate 5. The river was almost 10 feet over flood
stage. (Steve Bloom/The Olympian)
A Centralia neighborhood is submerged. Flood damage to a segment of the
interstate in the Chehalis area will keep the highway closed until Friday at the
earliest, a transportation department official said. STEVE RINGMAN / THE
SEATTLE TIMES
Flood waters from the Chehalis River inundate a neighborhood in
Centralia. STEVE RINGMAN / THE SEATTLE TIMES
You can't actually see Interstate 5 in this photo, it's under the flood water.
Notice the exit sign on the bottom of the photo, just a little left of center, and
the freeway overpass in the middle of the photo. Dec. 4, 2007. WA DOT
SR 6 under a massive mud slide near Pe Ell
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